The present invention relates to a printed circuit board, a manufacturing method therefor, and a metal-surface treatment liquid.
In recent years, as electronic devices have been required to have high functionality and the like, electronic parts have been becoming more integrated with a high density, and printed circuit boards and the like used for the electronic parts have also been becoming more miniaturized and higher in density. Under these circumstances, the width of metal wiring in the printed circuit boards is becoming narrower.
Generally, a printed circuit board is obtained by laminating one or more layers of metal wiring and one or more insulating layers. At this time, if adhesiveness between the metal wiring and the insulating layer is insufficient, a gap is formed between the metal wiring and the insulating layer. When water vapor or the like comes into the gap, electrical insulating properties deteriorate, or a short circuit or the like is caused between wirings.
In the related art, as a technique for improving adhesiveness between the metal wiring and the insulating layer, a technique of roughening the surface of the metal wiring to bring about an anchor effect is used. However, under the current circumstances in which the width of metal wiring is being increasingly narrowed, there are problems that roughening of the surface of the metal wiring is not easy, and high-frequency characteristics become poor due to the formed concavities and convexities.
Accordingly, as a technique for improving adhesiveness between metal wiring and an insulating layer without roughening the surface of the metal wiring, a method of treating the surface of the metal wiring with a triazine thiol derivative has been proposed (JP 2000-156563 A).